You probably have an idea of what a bike messenger’s job is like, either based on the many media depictions of the job, from “Quicksilver” to “Premium Rush,” or on the fact that in many cities, messengers do seem perennially hurried to the point of madness. Your impression is not wrong, because most messengers work for messenger companies doing piecework—they are paid by the job—so they have an incentive to do as many jobs as possible. That was not my job.